SRE-46: Upgrade Docker Postgres to 18.1-alpine3.23

[TimDiekmann]

Upgrades the Docker Postgres base image to 18.1-alpine3.23

🌟 What is the purpose of this PR?

Upgrades the Postgres Docker base image from version 17-alpine3.22 to 18.1-alpine3.23. This change only affects local Docker development, not production AWS.

🔍 What does this change?

• Updates the Postgres Docker base image in apps/hash-external-services/postgres/Dockerfile from 17-alpine3.22 to 18.1-alpine3.23

Pre-Merge Checklist 🚀

🚢 Has this modified a publishable library?

This PR:

• [x] does not modify any publishable blocks or libraries, or modifications do not need publishing

📜 Does this require a change to the docs?

The changes in this PR:

• [x] are internal and do not require a docs change

🕸️ Does this require a change to the Turbo Graph?

The changes in this PR:

• [x] do not affect the execution graph

🛡 What tests cover this?

• Existing tests should cover this change

❓ How to test this?

1. Checkout the branch
2. Start the development environment with Docker
3. Confirm that Postgres starts correctly with the new version

[CLAassistant]

All committers have signed the CLA.

[cursor[bot]]

PR Summary

Upgrade Postgres to 18 across Docker and RDS, and switch the bastion host to ARM (t4g, arm64 AMI).

• Postgres:
  • Docker: base image updated to postgres:18.1-alpine3.23 in apps/hash-external-services/postgres/Dockerfile.
  • AWS RDS Terraform: parameter group family -> postgres18 and engine_version -> 18 in infra/terraform/hash/postgres/postgres.tf.
• Bastion (Terraform module):
  • Instance type changed to t4g.nano in infra/terraform/modules/bastion/bastion.tf.
  • AMI lookup updated to arm64 Amazon Linux 2023 (al2023-ami-2023.*-kernel-6.1-arm64) with architecture=arm64, virtualization-type=hvm in infra/terraform/modules/bastion/main.tf.

^{Written by Cursor Bugbot for commit 49f74a042536e99e3ccaf39de4e9215e6b08d6e8. This will update automatically on new commits. Configure here.}

[semgrep-code-hashintel[bot]]

Semgrep found 1 ec2-imdsv1-optional finding:

• infra/terraform/modules/bastion/bastion.tf
  • L122-132 - Triage

AWS EC2 Instance allowing use of the IMDSv1